Use Smart Controls in Logic Pro
Go to View >> Show Smart Controls or simply press B to access Logic’s rack-ish system. Every in-built Logic instrument or effect has a pre-determined set of controls, in a nice graphical interface. You can, of course, cast everything away and create your own mappings and routings, as well as setting up definitions for minimum and maximum values, as well as scaling – the function between those two. Oh, and Logic’s Smart Controls windows also come with an in-built Arpeggiator that you can switch on for some MIDI note fun.